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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Is 10" of vacuum in crankcase normal?

  • Thread starter Thread starter starchiefus
  • Start date Start date Dec 27, 2007
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starchiefus

Member
Dec 17, 2003
43
1
7
San Diego
Jan 26, 2008
#21
  • Jan 26, 2008
  • #21
Vacuum in crankcase-Fixed

Thanks to everyone for their help, I replaced the intake gasket and manifold and that fixed the problem, I will note that there was a huge difference between the intake gaskets from my generic rebuild kit and the Felpro 1250's i ordered with the new manifold. I also went with a smaller carb Holley 390 and treated myself to a fuel pressure regulator.
So vacuum back up to 22", + holley fired up and idled smoothly right out of the box (never had a brand spanking new carb before, what a difference),= one happy camper.

Thanks again./Steve
 

zookeeper

Founding Member
Aug 25, 2001
3,415
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109
Rogue River, Oregon
Jan 26, 2008
#22
  • Jan 26, 2008
  • #22
If your car is a daily driver and fuel economy is a factor (I can't imagine it NOT being) then you will be thrilled with that 390 carb. They are great carbs and can support 400hp easily.
 
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